On the evolution, numbers and characteristics of close-binary supersoft sources.- White dwarfs with H/He burning as supersoft X-ray sources.- Hot high-gravity NLTE model atmospheres applied to supersoft sources.- Luminous supersoft X-ray sources in globular clusters.- The integrated X-ray spectrum of galactic populations of luminous supersoft X-ray sources.- Neutron stars can do it too if they want to.- SSSs as progenitors of the BHCs.- Simulation of the visual light curve of CAL 87.- Accretion disks in supersoft X-ray sources.- Supersoft X-ray sources in M31.- X-ray and optical observations of RX J0925.7-4758: Constraints on the binary structure.- The X-ray energy spectrum of RX Jo925.7-4758 with ASCA.- Optical photometry of RX J0019.8+2156 over the last three years.- Phase resolved UV spectroscopy of RX J0019.8+2156.- Optical spectroscopy of RX J0439.8-6809 and 1E 0035.4-7230.- Photometric observations of supersoft sources in the LMC.- Optical light curve and binary period of the supersoft X-ray transient RX J0513.9-6951.- Non-LTE model atmosphere analysis of the supersoft X-ray source RX J0122.9-7521.- Implications of light metals (Li?Ca) on NLTE model atmospheres for hot stars.- The long-term X-ray lightcurve of RX J0527.8-6954.- Interpretation of the long-term optical variations of RX J0019.8+2156.- ROAST monitoring of the LMC supersoft transient source RX J0513.9-6951.- Optical variability of the LMC supersoft source RX J0513.9-6951.- Optical and X-ray variability of supersoft X-ray sources.- Type Ia supernovae and supersoft X-ray sources.- Luminous supersoft X-ray sources as progenitors of type Ia supernovae.- A new model for progenitors of type Ia supernovae and its relation to supersoft X-ray sources.- Transient and recurrent supersoft sources as progenitors of type Ia supernovae and of accretion induced collapse.- ROSAT observations of symbiotic binaries and related objects.- X-ray properties of symbiotic stars: I. The supersoft symbiotic novae RR tel and SMC3 (=RX J0048.4-7332).- Multiwavelength observations of the symbiotic star AG dra during 1979-1995.- UV and X-ray monitoring of AG draconis during the 1994/1995 outbursts.- A candidate isolated old neutron star.- A systematic search for supersoft X-ray sources in the ROSAT all-sky survey.- A search for optical counterparts to supersoft X-ray sources in the ROSAT pointed database.- Catalog of luminous supersoft X-ray sources.